clinical fit training - optometry.co.il€¦ · fitting guide. each dx lens has ... - power of dx...
TRANSCRIPT
Clinical Fit Training
Product Overview
3
Lens Design
4
Patent-pending Vault design
The vault value describes the overall relative depth of the lens on the cornea. The goal is to determine the appropriate vault that provides complete apical clearance.Design gives the ability to “vault” over the vast majority of ectasias without bearingDesign results in substantially lower lens power:- Closer lens alignment to the cornea in conjunction
with the lacrimal lens results in significantly lower powers
- Enhances optical quality and improves Visual Acuity for the patient
- Lower lens power in conjunction with superior centration substantially reduces coma and minification
5
New Hybrid Skirt Design
ClearKone incorporates a new reverse geometry hybrid design that:
- Promotes all-day tear flow and movement
- Facilitates ease of removal
- Provides all-day comfort and corneal health
The lens lands on both the soft, defined as Outer Landing Zone (OLZ) and rigid, defined as Inner Landing Zone (ILZ) materials. The landing area is divided by the junction of the hybrid lens.
6
Vault and Skirt Curvature
ClearKone is available in 11 different vaults of which each can be ordered in 3 different skirt curvatures; flat, medium and steep.
The fit of the vault is independent of the fit of the skirt curve. Each should be fitted separately.
The vault diameter is ~7.4mm and includes the spherical
optic zone and reverse curve
7
ClearKone Diagnostic Set
22 lens diagnostic set:11 Vaults: 100 – 600µin 50µ steps2 Skirt Curvatures for each Vault: Medium and SteepDMV scleral cup inserterNaFL illuminating cobalt pen lightWratten filterFitting Guide
Each Dx lens has laser markings that indicate its lens type, vault
and skirt curvature
8
Streamlined Fitting Process
Linear vault fitting process minimizes chair time- Power of Dx
lenses are calibrated to change at the
same rate as the vault- All lenses within the fitting set will require the same
over-refractionCalculations that are normally needed with other lenses are unnecessary Once the over-refraction of a Dx lens has been determined, every other lens in the set will take the same over-refraction
Requires no topography
Fitting ClearKone is both consistent and predictable and requires minimum chair time and remakes.
9
Patient Candidates
ClearKone is Ideal for:
Oval/nipple keratoconus (emerging to advanced)
Central and the majority of decentered cones
Fitting success may be possible for:
Globus
Pellucid Marginal Degeneration
RK, PRK, LASIK induced ectasia
Most irregular corneas
10
ClearKone Terminology
Vault - The vault value describes the overall relative depth of the lens
Outer Landing Zone (OLZ) - Portion of the lens that lands on the soft material
Inner Landing Zone (ILZ) – Portion of the lens that lands on the RGP material
ILZ
OLZ
RGP/SCL Junction
11
ClearKone Terminology (con’t)
NaFL Thinning – refers to the appearance of a NaFLpattern in a lens with apical clearance to the cornea. A decrease of thickness of the tear layer will cause a decrease in fluorescence, resulting in an area of NaFLhaving a darker appearance than the area around it (Not black as with bearing)
ILZ Thinning
12
ClearKone Terminology (con’t)
Bearing – a black appearance as a result of contact of the cornea with the posterior of the lens, eliminating the presence of NaFL and the possibility of any fluorescence.
Central Bearing ILZ Bearing
13
ClearKone Terminology (con’t)
Pooling – complete uniform appearance of the NaFL layer (no variation in brightness)
Central Pooling
Fitting Process
15
Bubbles
Areas within the optic zone could result in trapped air bubbles if lens not inserted properly
Air bubbles affect the appearance of NaFL pattern -critical to eliminate them prior to evaluating fit
Bubbles are ALWAYS representative of an insertion error – NOT a fitting error
Must remove lens and re-insert – making certain bowl of lens is filled to the TOP with solution
16
Proper Insertion Process
To increase the comfort of the fluorescein and to minimize insertion bubbles, fill the bowl of the lens with 1 drop of fluorescein and fill the remainder of the bowl completely to the top with non-preservedsaline.
17
Proper Insertion Process (con’t)
Fill the lens while holding it horizontally on the DMV scleral cup (included in the Dx set).
Have the patient lean forward and tuck their chin to chest. Nose perpendicular to the floor.
Bubbles are less likely to occur if patient maintains fixated gaze straight to the floor.
18
Proper Insertion Process (con’t)
Retract the upper and lower lids and elevate the lens onto the center of the cornea, displacing the saline.
Be careful not to push the lens too forcefully upon insertion.
- This can induce corneal suction resulting in edema
19
Proper Insertion Process (cont.)
Check for bubbles under the lens with the NaFLilluminating cobalt pen light (provided in Dx set)Bubbles cannot be displaced by lens manipulation –must remove and re-insert
20
Key Fitting Principles
The fitting of ClearKone is based on the concept of fitting on overall sagittal depth rather than varying the base curve in relation to the irregular cornea.
- The fit of ClearKone depends upon the depth of the lens clearing the elevation of the cone, rather than a match in curvature
The fitting process involves individually fitting two different areas of the cornea:
- Central
–
determining the appropriate vault needed to clear the cone and provide complete apical clearance.
- Peripheral
–
determining the skirt curvature
that places the proper distribution of support within the landing zones.
21
Evaluating NaFL
Patterns
The key to determine the proper ClearKone fit is to evaluate the lens/cornea relationship using high molecular weight NaFL (i.e. FluoreSoft®)
NaFL evaluation must be done within 3-5 minutes after insertion, because the tear flow will thin the NaFL and give a false appearance/interpretation. (Should not let patient sit in waiting room for 15+ minutes)
Critical to eliminate any central touch when fitting. Even the lightest touch or “feather touch” can cause patient discomfort.
Critical to use a Wratten filter (provided in Dx set) to enhance the contrast of the NaFL pattern. Makes fine tuning the skirt curve much easier and will save chair time.
22
Corneal Changes
For patients who are being re-fit from RGPs, SynergEyes A, KC or PS (and sometimes even soft/soft torics)- Once the pressure of the predicate lens is removed,
the cornea will most likely return to its natural shape- You should expect topographical changes- Critical to have complete apical clearance on first fit
lenses- On follow-up if patient complains of discomfort or
reduced wear time –
check for central bearingMay need to re-order deeper ClearKone lenses
23
Example Topo
Changes of ClearKone Patient
Predicate Lens: Rose K
Successfully Wearing
ClearKone for over 1
year
24
Ideal ClearKone Fit
OLZ Bearing
ILZ Thinning
RGP/SCL Junction
Apical Clearance
25
Step 1: Determine
Vault
To determine the proper vault, begin with the 250µ
Vault value in the Medium skirt curve and check for:
ORCentral Bearing
Central Pooling
26
Step 1: Determine
Vault
Starting point is the 250µ
/ medium skirt Dx lens.
If central bearing
is seen, increase the vault in 100µ
increments, until
apical clearance is achieved.
Central Bearing
Vault too shallow
27
Step 1: Determine
Vault
•
Ideal vault fit = 100µ over first bearing
•
Complete apical clearanceRemember: Even the lightest touch or “feather touch” can cause patient discomfort
Ideal Vault Fit
After a few minutes of wear, the patient will tell you if you have bearing because the lens will not be comfortable.
Apical Clearance
28
Step 1: Determine
Vault
At the 250µ
/ Medium starting point.
If pooling
is seen, decrease the vault in 100µ
increments until
the first bearing is observed.
Central Pooling
Vault too deep
29
Step 1: Determine
Vault
Vault decreased 100µ
When first bearing is observed –
increase the
vault by 100µ
and re- evaluate the corneal
clearance for apical clearance.
Central Bearing
Vault too shallow
30
Step 1: Determine
Vault
Vault increased 100µIf the increased vault now results in apical clearance, you have reached the endpoint.
If the increased vault still results in bearing, increase the vault 100µto reach the fitting end-
point.Ideal Vault Fit
Apical Clearance
After a few minutes of wear, the patient will tell you if you have bearing because the lens will not be comfortable.
31
Step 2: Determine Skirt Curvature
Evaluate skirt only after proper vault determined and is on eyeGOAL: on most patients, best fit landing area achieved when NaFL thinning is observed in ILZ and bearing in the OLZ.Lens will exhibit movement very similar to soft lens.
ILZ Thinning
OLZ Bearing
RGP/SCL Junction
Patient comfort will greatly validate final fit
Ideal Skirt Curve Fit
32
Step 2: Determine Skirt Curvature (con’t)
Start with the Medium skirt curveEvaluate landing area at 3 and 9 o’clock positions with the slit beam perpendicular to the area being observed- It is critical to have the slit beam positioned
perpendicular to the area being observed in order to properly illuminate the area for evaluation
Slit beam is positioned perpendicular to the 9
o’clock position to effectively evaluate the
landing zone
33
Skirt Curve too Flat
If bearing observed under ILZ and thinning observed under OLZ –
change to the STEEP skirt curve
Thinning under OLZ – Steepen Skirt
34
Skirt Curve too Flat
If equal bearing observed under both ILZ and OLZ – change to the STEEP skirt curve
ILZ Bearing
OLZ Bearing
35
Skirt Curve too Flat
If pooling observed under the OLZ, and bearing is observed under ILZ –
change to the STEEP skirt
ILZ Bearing – Steepen Skirt
36
Skirt Curve too Steep
If pooling observed under the ILZ–order the FLAT skirt curve
37
Patient comfort is optimized when NaFL
pattern shows slight diffusing beneath the rigid/soft junction
Determining Proper Skirt Curvature
NaFL Diffusing Beneath Junction
38
Step 3: Determine Final Lens Power
When an ideal NaFL pattern is achieved, over-refract to determine final lens power
If the over-refraction is greater than 4.00D, adjust for vertex distance.
Lenses in the fitting set vary in power from -1.00D to -14.50D sphere power depending on the vault depth selection.
- A laminated card is provided in the Dx set indicating the power of each lens
Tips for Achieving Success
40
Evaluating NaFL
Patterns –
Timing is Critical!
1 minute after insertion 3 minutes after insertion
IDEAL WAIT TIME
7 minutes after insertion 16 minutes after insertion 31 minutes after insertion
41
NaFL
Pattern 1 Minute after Insertion
NaFL
pattern 1 minute after insertion –
lens still settling
42
NaFL
Pattern 3 Minutes after Insertion
NaFL
pattern 3 minutes after insertion –
ideal amount of fluorescein to evaluate the fit
43
NaFL
Pattern 7 Minutes after Insertion
NaFL
pattern 7 minutes after insertion –
tear flow has thinned the NaFL
and gives a false indication of bearing
44
NaFL
Pattern 16 Minutes after Insertion
NaFL
pattern 16 minutes after insertion –
fluorescein dissipated even further
45
NaFL
Pattern 31 Minutes after Insertion
NaFL
pattern 31 minutes after insertion –
fluorescein almost completely dissipated. The difference in fit of the ILZ & OLZ
can no longer be determined.
46
Subtle NaFL Pattern Differences -
Skirt
Subtle differences in NaFL patterns affect lens fit. Which of the following is the ideal skirt curve?
Example 1
Example 2
Example 3
47
Subtle NaFL Patterns –
Example 1
Example 1: Skirt Curve too Steep
ILZ Pooling
OLZ Pooling
48
Subtle NaFL Patterns –
Example 2
Example 2: Skirt Curve Too Flat
ILZ Bearing
49
Subtle NaFL Patterns –
Example 3
Example 3: Ideal Skirt Curve
ILZ Thinning
OLZ Bearing
50
Making Changes at Follow-Up
If a vault change is needed at follow-up, the lens power will also need to be adjusted The chart included in the Dx set lists the Rx for each vault – add/subtract the required change in lens power by determining the Rx with the new vault- Example: Change vault from 300μ
to 350μ
–
difference in Rx is - 1.50D.
- The Rx on the 350μ
lens is -1.50D greater than the Rx on the 300μ.
51
Making Changes at Follow-Up (con’t)
If a power change is required in addition to a vault change, the power change must be added to the power change required by the change in vault
- Example: Change vault from 300μ
to 350μ
and need an
additional -.50D
New lens power is -2.00D from original lens power
52
Fitting challenges
Ectasia extends beyond landing zone
Irregular landing pattern –unable to achieve an even distribution of landing zone
Post-graft patients – fitting success can be possible but landing zone may fall on the graft-host interface
Highly irregular or asymmetric landing pattern
- Often seen in advanced PMD patients
Final fit and ultimate success is not always
predictable purely based on corneal topography
Unsuccessful Fit
53
Where to start
Fitting ClearKone is different than any other KC lens –including SynergEyes KC- Disregard all conventional fitting methods and commit to
learning curveAfter ~3-4 patient fits, the fitting process will go very quickly and be straightforward / predictable - Give yourself some extra time initially
Don’t start with the most extreme patients who have failed with every other product instead, we suggest
Newly diagnosed patientsRGP patients wanting better comfort/acuityPiggybacks wanting improvementsFailed SynergEyes KC patients
54
Things to remember
Critical to eliminate any central touch when fitting. Even the lightest “feather touch” can cause patient discomfort.
For patients being re-fit from RGPs, SynergEyes KC, A, PSor even soft lenses- Cornea will most likely return to it’s natural shape once the pressure
of the predicate lens is removed
- May need to re-order deeper lenses after the cornea re-normalizes
Patient comfort greatly validates final fit in ClearKone
Patient training is critical- Proper insertion- Removal easier than KC lens but still requires training- Proper lens care critical (ONLY Non-preserved products)- Proper wear time -
daily NOT extended
- Build wear time over 5-7 days
Case Study
56
ClearKone Case Study
Patient JS
Diagnosis: keratoconus
Contact lens history:
- RGP’s since 1959 (most recent: Rose K)
- Re-fit into SynergEyes KC in 2006 and was able to wear for 8 hours per day
Goal:
- Increase comfort OU
- Increase wear time
57
K’s 48.40 x 43.20
OD
ClearKone Case Study (cont.)
58
ClearKone Case Study (cont.)
Vault Selection250μ vault
Slight “Feather Touch”
59
ClearKone Case Study (cont.)
Vault Selection350μ vault – Ideal Fit
Apical Clearance
60
ClearKone Case Study (cont.)
Vault Selection150μ vault
Central Bearing
61
ClearKone Case Study (cont.)
Skirt Selection350μ vault with Medium skirt
ILZ Thinning
62
ClearKone Case Study (cont.)
Skirt Selection350μ vault with Flat skirt
ILZ Bearing
Patient Insertion and Removal Instructions
64
Lens Insertion: Patient Instructions
65
Lens Insertion: Patient Instructions (cont.)
66
Lens Insertion: Patient Instructions (cont.)
67
Lens Removal: Patient Instructions
1.
Wash and dry hands.
2.
Hands must be completely dry for successful removal.
3.
Do not use lubricating drops prior to removal.
4.
Make the “OK”
sign with the thumb and forefinger.
68
Lens Removal: Patient Instructions
(cont.)
Every patient should view the insertion & removal
video at www.synergeyes.com
5.
Look straight ahead.
6.
Grasp the lens at the 6 o’clock position.
7.
Allow air underneath the soft skirt of the lens.
8.
Lift lens away from eye.
69
Lens Care: Patient Instructions
Patients must digitally clean their lenses each day prior to overnight storage for disinfection. For rinsing use only a preservative free saline solution such as Unisol®4. For disinfection use Clear Care® or Oxysept®Ultracare® Formula Peroxide Disinfection System.
70
Lens Care: Patient Instructions (cont.)
To clean the lenses, place the lens bowl-side up in the palm of the hand and apply a few drops of saline.
With the pad of the finger gently rub the entire lens in a circular motion against the palm of the hand.
Be sure to thoroughly clean the entire lens and then rinse it well in a steady stream of saline.